Screen doors fitted to the perimeter regions of windows and doors have long been a commodity in households as well as businesses. Certain types of screen doors that have upper and lower track members and some form of a housing generally attempt to lock in a screen door handle in some fashion in an open position where the screen is withdrawn. One form in the prior art of locking such a screen is to lock a handle in the upper and lower portions along a guide rail. However, the handle which is adapted to extend the screen from some form of the base housing is not well adapted to address any form of moment (torque) about a transverse axis. In other words, there is tremendous possibility for a handle to rotate about an axis orthogonal to the plane of the screen thereby having a “cockeyed” handle with respect to the stationary frame items. This problem is amplified in situations where the screen places a tension in a first direction upon the handle and some form of lateral force in the second lateral direction must withstand this tension to keep the screen open. Further, it is desirable to have the screen shut and have some form of a spring to wind up the screen within a housing in a stored position.
One particular problem with repositioning a screen from an open position to a closed position is trying to finesse an equal amount of force to counteract the “holding force” to position the handle and screen in an open orientation with the screen extended. Normally the holding force is some sort of fractional engagement or temporary locking engagement such as extending some sort of knob around a constructed portion where the constructed portion slightly expands to have the knob extension fit therein. Of course this generic description can address a plurality of types of prior art mounting systems but the gist of such a mechanical apparatus requires some form of deformation of material to lock and unlock the handle to and from the open position. This generally requires perhaps some form of inertia or at least a focused amount of force with holding the handle in such an open position.
In other words, when opening a handle in prior art forms, there is some form of snapping action to lock such a handle open to counteract the force of the spring winding up a screen. It has been found to be problematic that when trying to close the screen, one of the two locking members at the upper lower portions will disengage while the other locking member remains engaged, causing the cockeyed arrangement of the handle which is very undesirable. Further, given the constraints of the ability to place reinforcement members to prevent such a situation, there appears to be little hope for preventing such misalignments of the handle from occurring. Further, once the handle is past the high resistance on any locking portion, there is essentially a lengthy free pull where the tension in the spring can translate the force there along the screen and the handle accelerates until slamming up to the base housing. Such an impact can cause injury to toes and fingers as well as cause general wear and tear on the screen assembly and possibly cause damage thereto.
Therefore, it is desirable to provide a system where a handle can remain open or even at intermediate locations where a counterbalancing force will occur at a plurality of locations and not just at an extreme open location. Such a system is desirable to allow for intermediate positioning of the handle, preventing a slamming action of the handle and to further aid in preventing any cockeyed arrangement of the handle with respect to the upper lower housing members.